The shell of a snail is made up of different units joined together.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question states that the shell of a snail is made up of different units joined together. We need to determine if this statement is true or false.

2. **Identifying the Structure of the Shell**: The shell of a snail is known as an exoskeleton. It serves as a protective covering for the snail.

3. **Composition of the Shell**: The shell is primarily made up of calcium carbonate. This material is hard and provides protection to the snail.

4. **Analyzing the Units**: The shell is not made up of multiple different units; instead, it is formed as a single unit of calcium carbonate. This means that the shell is a continuous structure rather than a collection of separate parts.

5. **Conclusion**: Since the shell is made of a single unit rather than multiple units, the statement in the question is false.

6. **Final Answer**: Therefore, we conclude that the statement "The shell of a snail is made up of different units joined together" is false.

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